SEC Form 4

FORM 4		UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940	OMB APPROVAL OMB Number: 3235-0287 Estimated average burden hours per response: 0.5
	Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

1. Name and Address of Reporting Person* MIDDLEKAUFF W BRADFORD (Last) (First) (Middle) C/O TOURMALINE BIO, INC. 27 WEST 24TH STREET, SUITE 702 (Street) NEW YORK NY 10010 (City) (State) (Zip)	2. Issuer Name and Ticker or Trading Symbol Tourmaline Bio, Inc. [ TRML ]	5. Relationship of Reporting Person(s) to Issuer (Check all applicable) Director 10% Owner X Officer (give title below) Other (specify below) CBO, GC and Secretary
	3. Date of Earliest Transaction (Month/Day/Year) 10/19/2023
	4. If Amendment, Date of Original Filed (Month/Day/Year)	6. Individual or Joint/Group Filing (Check Applicable Line) X Form filed by One Reporting Person Form filed by More than One Reporting Person
	Rule 10b5-1(c) Transaction Indication Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Common Stock	10/19/2023		A		69,201(1)	A	(2)	69,201	D

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares
Employee Stock Option (Right to Buy)	$7.9(3)	10/19/2023		A		124,991(3)		(4)	06/17/2033	Common Stock	124,991(3)	(3)(5)	124,991	D
Employee Stock Option (Right to Buy)	$9.46	10/23/2023		A		46,774		(6)	10/23/2033	Common Stock	46,774	$0.00	46,774	D

Explanation of Responses:

1. 32,839 of these shares are subject to a repurchase option in favor of the Issuer in the event that the Reporting Person's continuous service is terminated. Such repurchase option shall lapse in equal monthly installments until such shares are fully vested on June 1, 2026.

2. Received in exchange for 867,500 shares of common stock of Tourmaline Bio, Inc. ("Tourmaline") pursuant to an Agreement and Plan of Merger dated as of June 22, 2023 (the "Merger Agreement") by and among Tourmaline, the Issuer and Terrain Merger Sub, Inc., a wholly owned subsidiary of the Issuer ("Merger Sub"). Under the terms of the Merger Agreement, on October 19, 2023, Merger Sub merged with and into Tourmaline (the "Merger"), with Tourmaline surviving the Merger as a wholly owned subsidiary of the Issuer. Upon the closing of the Merger, each share of Tourmaline common stock was converted into the right to receive 0.07977 of a share of the Issuer's common stock, after giving effect to a reverse stock split of the Issuer's common stock of 10-for-1. Subsequent to the Merger, the name of the Issuer was changed from Talaris Therapeutics, Inc. to Tourmaline Bio, Inc.

3. Upon the closing of the Merger, each outstanding option to purchase shares of Tourmaline common stock was assumed by the Issuer and converted into an option to purchase the Issuer's common stock, on the same terms and conditions as were applicable to such Tourmaline stock option prior to the Merger, as adjusted for the exchange ratio and the reverse stock split.

4. The shares subject to the option vest as to 25% of the shares on June 14, 2024 with the remainder vesting in the following 36 equal monthly installments, subject to the Reporting Person's continued service on each such vesting date.

5. Received in exchange for a stock option to acquire 1,566,900 shares of Tourmaline common stock pursuant to the Merger Agreement.

6. The shares subject to the option vest as to 25% of the shares on October 23, 2024 with the remainder vesting in the following 36 equal monthly installments, subject to the Reporting Person's continued service on each such vesting date.

Remarks:

	/s/ W. Bradford Middlekauff	10/23/2023
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.